Questions tagged [electron]

Anything related to the behavior and properties of electrons, i.e. the elementary subatomic particles accounting for electrical conduction in most solid materials, especially metals.

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Do electrons flow from higher to lower or lower to higher potential?

I have seen countless sites saying electrons flow from higher potential to lower potential, but then again I have seen many saying that electrons flow from lower potential to higher. I have always ...
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Are vehicle electrical components powered from the negative side?

still trying to get my head around electron flow as opposed to conventional current regarding automotive electrical circuits. There seems to be a ton of conflicting information/advice out there so I'm ...
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731 views

How is current the derivative of charge

If electric current is the time rate of CHANGE of charge. Then if I have a DC fixed current flowing into a resistor, same amount of charge is always flowing to that resistor, hence the derivative of ...
191 views

The probability that an electron occupies the fermi level at 0K

I was trying to find the probability that an electron occupies the Fermi level at 0K. Fermi function: {exp[(E-Ef)/kT] + 1}-1; (k = 8.314 J/mol/K) According to my calculations, the answer would be 0.5. ...
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49 views

3 Phase Motor to DC Output

In a standard car alternator there is are 3 diodes that keep each of the phases from ever pulling electrons. There is then a capacitor to smoothens it all out. However how is it possible that the ...
60 views

KCL when rate of electron flow is given ; To include electron sign or not

Q) We have to determine the I. Magnitude of electron charge is 1.6 x 10^-19C. I have fundamental confusion in this problem. Should we consider the negative charge of electron while doing the problem. ...
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1 vote
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Generation of electrostatic induction

I need to generate a 500 volt electrostatic charge. How can I do this? I don't have a Van de Graaff generator. What are some practical suggestions? Basically I want to do an experiment in which I need ...
26 views

Repelling charges and current flow

The electrostatic force between two like charges is repelling. This concept is fairly clear to me with Coulomb's law and electric fields. So two electrons will repel each other. Given this statement, ...
108 views

Why are low band gap semiconductors (like silicon) not ideal for most solar cells? Are their atoms ionized by higher-energy photons?

Most sources on the web say that 1.3 eV or 1.4 eV is 'ideal' for most solar cells... What happens to lower-gap, gapless or overlap materials (conductors)? Are they ionized, rather than sending their ...
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Why is there EMF present when there is no current?

Current means the rate of flow of charge. Electrons are the ones that carry charge in current. From the definition of EMF (electromotive force), When no current is drawn from cell, the potential ...
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159 views

What does charge on an electron mean?

As I have read , charge is electrons , protons or neutrons. Now , according to definition of current , current is the rate of flow of charge I.e flow of electrons. Then , I=Q/t . Unit of Q is coulomb &...
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1 vote
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Majority Charge carriers and electron holes

Suppose I have an extrinsic semiconductor made of silicon and doped with phosphorous. Now, phosphorous has one more electron than silicon. After replacing one silicon atom, and taking its place, the ...
76 views

Shelly 1 Configuration

I am trying to implement the Shelly 1 switch for an electronic device I have. The electronic device has an open collector output channel (AUX1). It also has two output pins Z8 and C. When Z8 and C are ...
86 views

Can current flow from positive to positive in real life

How to implement a circuit diagram where there are 2 batteries and negative to negative have load and postive to positive have some load. How to implement, like build in real life this ...
2k views

Is there a mnemonic to remember direction of current flow?

I have always stumbled when remembering which current flow notation to use. In my mind, it's by default conventional current flow. But, I also have in mind electron flow notation. Do you know of a ...
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How many newtons are there in one coulomb of charge?

Or, I should have said, how many newtons of force does one coulomb of charge exert? At a distance, presumably, of one meter? Since N/C is supposedly equivalent to V/m? P.S. What are the values for a ...
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Removing collected charges in a IC CMOS circuit exposed under a 30keV electron beam source

I would like to know if there is any mechanism (for example UV light exposition) to remove charges collected in an IC CMOS circuit that was exposed under a 30keV electron beam source. Presumably, ...
578 views

Can a floating capacitor terminal be used to collect electrons?

I want to collect charge from an electron beam source. For that, I'm proposing to put a floating capacitor with its bottom terminal floating and directly exposed to the electron beam gun. The top ...
1 vote
128 views

Why does current continue flowing in a circuit?

Sorry for the amateur question, but I'm having trouble understanding this phenomenon. In a closed circuit, electron current flows from the negative terminal of a battery to the positive terminal. But ...
64 views

Signal interference in receiving antenna?

I’ve been scouring the interweebs for some insight into how electrical signals travel in a wire. More specifically, I cannot wrap my head around how a receiving antenna works with hundreds if not ...
6k views

In which direction do electric signals flow?

We know that electrons move from the negative to positive terminal, and that holes flow in the conventional direction of current - from the positive to negative terminal. I've always assumed that this ...
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Electrons flow in Li-ion Battery

I’m new to electricity, and I’ve got a question about electrons flow inside a Li-on battery. A lot of articles and videos show us only Li+ ion flows from anode to cathode through electrolyte during ...
73 views

How do I make a “directed” spark gap?

(Originally asked on engineering StackExchange, I was directed to ask it here) For a project, I need to create a spark gap that only triggers when there is a conducting material between the 2 contacts....
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1 vote
360 views

How does a single phase shared neutral circuit actually work, physically?

Okay so this is a two part question. First Question is probably more of an ELI5 question. But I am a fairly experienced electrician (NOT AN ENGINEER mind you.) but I have a generally good working ...
275 views

How can electrons in a tungsten filament release infrared light photons?

I have a question regarding electric circuits, specifically when it comes to converting electromagnetic energy into light in a light bulb (tungsten)filament. How can an electron in a tungsten atom of ...
1 vote
61 views

Mobility of electrons vs holes in semiconductors (intrinsic vs extrinsic)

I was reading my class notes and it was written that electrons are more mobile than holes because the effective mass of electrons are lower than that of holes. (μ=eτ/m*) I checked online to find the ...
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What does the fermi-level increase in reverse-bias?

Fermi-level tells us the probability of finding an electron at 50%. When you look at an energy band diagram in reverse-bias you can see the Fermi-level increases in the p-type semi-conductor. Why does ...
40 views

In an energy band diagram why is the valance band in the p-type have more energy then n-type?

I am having trouble understanding energy band diagrams. In an energy band diagram of a semi-conductor during equilibrium the valence band of the p-type is higher then n-type meaning electrons in the ...
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Why does a p-type conduction band have higher energy then n-type conduction band in a p-n junction?

In an energy band diagram that represents the p-n junction (during equilibrium) the p-type conduction band has greater energy then an n-type conduction band. Why does the p-type have greater energy ...
114 views

Geometric information within 1D streams of electrons/photons

How is light—or actually any frequency in the EM spectrum—self-encoding and self-modulating 3D info in its 1D self, so that it “knows,” once it strikes a surface, to discharge all the data perfectly ...
158 views

I have always gotten great answers on this site so I thought I'd give this one a shot. In looking into 5G technology, I found that it radiates at 60 GHz, which apparently is in the oxygen absorption ...
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1 vote
75 views

Why Protons travel through the membrance but electrons travel through the wire?

In the case of having two electrodes (anode and cathode). I will always hear that positive ions will jump from one electrode to the other causing the electricity to flow the wire. How come only ...
2k views

What actually happens to electrons in a circuit when work is done at a component?

As the title. Between when voltage is higher; before the electrons reach the component, and afterwards.
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What are the typical paths of holes and electrons in an unbiased PN junction?

Can anyone tell me the typical paths of holes and electrons in an unbiased PN junction at equilibrium? In terms of diffusion currents, is that only holes (majority carriers in the the P-Type) ...
162 views

logic gates. What makes it what it is? [closed]

Does anyone know what it is about each logic gate that makes it "and, or not xand, etc." like, is it a different shape, therefore causing electrons to go different places when a charge is ...
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Does hole concentration fall below the intrinsic concentration, if Si is doped with pentavalent impurities?

If we increase N type doping in a pure Silicon then according to the equation $$P_n=\frac{n_i^2}{N_D}\text.$$ Then mathematically, hole concentration is less than $n_i$, if $N_D>n_i$. Why does ...
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How do capacitors in series work?

If capacitors are connected in series with a vltg source, then how would each plates get the polarity? For a single capacitor, the electrons from one plate are pumped by the source towards the other ...
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1 vote
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Metal semiconductor Junction

As we know in normal p-n junctions is formed by doping on a single semiconductor so that material continuity is maintained which facilitates the movement of charge carriers between two regions. But in ...
56 views

Movement of electron in ac current

Movement of electron direction in ac current is continuously changing which leads to more collision of electrons then dc current.From this can we conclude that ac current heated the wire more than dc ...
22 views

Antenna Theory and Electron Paramagnetic Resonance

Hi I am trying to understand why and how Antenna Theory works as it does. I can only link Antenna Theory to Electron Paramagnetic Resonance @ 2.8Ghz but I do not know how I can link the resonant ...
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Flyback and electron flow

sorry in advance as english is not my mother tongue. I have been using electron flow point of view for ages for analyzing and designing circuits (disclaimer: I have a background in computing - not ...
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182 views

Diode AND gate electron flow [closed]

In a two input diode AND gate, when both inputs are low, both diodes conduct and pull the output down to a low voltage. How can the electrons flow to the input of the AND gate, when the input is ...
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107 views

What happens to an electron when he returns home after doing his job?

When an electron turns on a LED, a lamp or moves an engine, I guess the electron is not lost, what happens is that it loses energy What really happens, "returns home" in an orbit lower than he had ...
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Finding free electron concentration to check authors' calculations for electron drift velocity

I am currently studying Practical Electronics for Inventors, Fourth Edition, by Scherz and Monk. Chapter 2.5.1 How the Shape of a Conductor Affects Resistance presents the following image: I ...
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254 views

In what pattern does the electrons get emitted from cathode in thermionic emission?

We have structure with an cathode and filament at the center. A cylindrical shaped anode with cavities surrounds the cathode (fig 1). When the cathode get heated the electrons are emitted from cathode ...
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Calculation for the distance between maximum swings in the drift distance of electrons

I am currently studying the textbook Practical Electronics for Inventors, Fourth Edition, by Scherz and Monk. In section 2.4.1 Applying a Voltage, the authors have written the following: In the case ...
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Voltage drop in a conductor

My textbook, Practical Electronics for Inventors, Fourth Edition, by Scherz and Monk, says the following in section 2.3.1 The Mechanisms of Voltage: In regard to potential energies of free ...
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How can electricity be positive when electrons are negative?

I don't understand how can a for example a battery be positive charged when the electrons are negative charged? I've read that protons are positive but they can't move so are all electricity negative?
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